Hello,I got from a friend an old "SmartRobot" vacuum robot. its virtual wall works for 2 hours each time i turn it on, the robot on the other hand can be scheduled. I am looking for a hack to make my virtual wall stay on. if you think I will have a battery problem I will just buy some DC supply to replace the batteries, so no worries.attached is the circuit (not so good of a picture, I think the "name" of the circuit is "Dummy0418").I'm pretty sure my robot is like "deebot" from the pictures, the wall looks the same. (attached also).

Roomba added a feature to its Virtual Walls several years ago where a radio signal from the robot would turn on all the VW's when cleaning. Short of such fancy work a number of possibilities exist.It is probably not possible to change the timer inside this VW because it is probably in the code for the microcontroller or other custom IC on it.

One thing to test is just keeping the button permanently pressed to see if this defeats the timer, taping it down or something.

One possibility: tape down the on/off button to permanently "ON", and power with an A/C adapter. Plug this adapter into a wall plug timer device available in hardware stores or online. Then the timer could be set to match the robot schedule. The elaborate "smart home" or radio controlled wall power control, remote lamp control etc. products might also be used.

A variation on this is to replace the VW on/off button with a relay which is controlled by a separate timer. There are a number of hobby circuits online which are for making a timer controlled relay with digital timer IC's.It is possible the on/off button has to be released to start the VW, so this option is needed then.

It is possible various ways to detect when a robot leaves its charging dock, with microswitches and what not, even tapping indicators in the dock if present (I use one on a Samsung bot to control a kitchen timer for run time reading). Someone even used some device part of a smart home or remote power control system (some work with signals over the power lines, some through WiFI or smart phones etc.)A number of connections could then be made by radio with the relay used on the VW on/off button.

Another possibility is a circuit added to the VW which detects when it shuts off and automatically turns it back on again, replacing the on/off button with added electronics controlling a relay.

It all depends on what is on hand and how much it is worth to spend on -- and what resources and skills are available for DIY electronics projects.

I used this to power VW's off of wall A/C adapters; there are 3v adapters available but USB chargers most common and cheapest.

I am not sure this type of solid state relay on ebay can be used to connect the contacts on the on/off button, which can sometimes be too low a voltage -- testing needed. You can time the VW power supply, but what about the press-on, press off button? Some VW buttons will ground the contacts, some will apply the 3v battery supply voltage (I did such things interfacing a kitchen clock timer). Measure the contacts with a volt meter. Maybe your ebay timer will work, time will tell. Sometimes I would use a small 5v SPDT reed mechanical signaling relay with a logic IC set up for momentary one shot action: supply power closes the relay and an IC then shuts off the relay to open, leaving open until reset when power supply goes off. Power the VW and relay circuit through the ebay timer. A 555 IC is specifically for one-shot pulse outputs, but other things can be configured for this as well, comparators and flip-flops. Depends on what you need (relay supply through IC normally supplying power, and when the relay closes supplies an input to switch to a latched off state).

It might be possible to just put a sufficient capacitor in series with a relay, so it closes until the capacitor charges and opens the relay, while a high resistance bypass discharges the capacitor when power is off. I can do some experiments to find a circuit if needed, parts on hand.

[edit] Another simple one shot to an on/off switch which connects the 3v power momentarily to an input might be made of a PNP transistor switched on by grounding the gate, which if to a capacitor would be like the relay above. All such parts inexpensive from China on ebay, though with slow shipping. I have used BC557 (547 for NPN) from projects on the web. Works on very low voltages, very small voltage drop. I suppose some small MOSFET but not familiar.

To use a power line timer with the device requiring a push-and-release On/Off button to operate, when the button works by applying the 3v battery supply across the button contacts, a capacitive coupling sometimes works to convert the power line onset into a pulse to activate the device. The capacitor delivers the power supply until it charges and stops the output. When the power supply cuts off it discharges gradually for a subsequent repeat.

Device power button must be checked for operation by applying 3v vs grounding etc.

The diode insures only a positive pulse is delivered to the device without any abnormal loading of its circuits in case that would affect it. Bracketing the capacitor in resistors provide a discharge path with delay. The diode has a voltage drop around .7v so some extra voltage is applied from the power supply adjusted by R1/R2, possibly not necessary.

Capacitor 1uf, R2,3 47K, R1 15K could be tried to start with. The larger the capacitor the bigger the pulse.D1 switching diode 1N4148. Does not need perfboard mounting.

Reduction of 5v USB AC adapter power to 3v battery previously shown using diodes in series.